[Community-acquired pneumonia]. / Ambulant erworbene Pneumonien.

CLINICAL ISSUE: The diagnosis of community-acquired pneumonia (CAP) is often not possible based only on the clinical symptoms and biochemical parameters. STANDARD RADIOLOGICAL METHODS: For every patient with the suspicion of CAP, a chest radiograph in two planes should be carried out. Additionally, a risk stratification for the decision between outpatient therapy or hospitalization is recommended. METHODICAL INNOVATIONS: Based on the evaluation of the different radiological patterns as well as their extent and distribution, a rough allocation to so-called pathogen groups as well as a differentiation between viral and bacterial infections are possible; however, because different pathogens cause different patterns an accurate correlation is not feasible by relying purely on imaging. ACHIEVEMENTS/PRACTICAL RECOMMENDATIONS: The radiological findings serve as proof or exclusion of pneumonia and can also be used to evaluate the extent of the disease (e.g. monolobular, multilobular, unilateral or bilateral). In cases of prolonged disease, suspicion of complications (e.g. pleural effusion or empyema, necrotizing pneumonia or abscess) or comorbid conditions (e.g. underlying pulmonary or mediastinal diseases) computed tomography is an important diagnostic tool in addition to chest radiography. Ultrasound is often used to diagnose pleural processes (e.g. parapneumonic effusion or pleural empyema).

[Imaging in oncology: terms and definitions]. / Onkologische Bildgebung: Begriffe und Definitionen.

Oncologic imaging includes the morphological description of the primary tumor region for an accurate classification of the tumor and lymph node stage and whether distant metastases have occurred according to the TNM staging system. Knowing the stage of the disease helps to plan the treatment and to estimate the prognosis. In clinical routine this is accomplished by conventional imaging techniques, such as ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI). Additionally, oncologic imaging is essential in treatment monitoring to visualize and quantify the effect of cancer therapy according to response evaluation criteria in solid tumors (RECIST) and World Health Organization (WHO) criteria. The tremendous development in oncology and technical innovations in imaging represent a particular challenge for radiology.

Bronchial reactivity in hyperresponsive patients and healthy individuals: demonstration with high resolution computed tomography.

OBJECTIVE: High resolution computed tomography (HRCT) was used to assess the extent of bronchial reactivity after inhalative bronchoprovocation and dilation in hyperresponsive patients and healthy subjects. PATIENTS AND METHODS: Patients with mild intermittent asthma, 15 with a >20% decrease in FEV1 and a >10 mmHg (PC20+) in PaO2, 12 with a <20% decrease in FEV1 and a >10 mmHg (PC20-) in PaO2 after provocation, and eight healthy humans were included in the study. Changes in cross-sectional area in a total of 1256 bronchi and in bronchial wall area (792 bronchi) were evaluated after histamine-triggered bronchoprovocation and salbutamol-induced bronchodilation at high lung volumes (FVC 80%). Data were compared with the results of pulmonary function tests (FEV1, PaO2, PaCO2). RESULTS: In all groups, a significant decrease in bronchial cross-sectional area (P<0.001) and a significant increase in bronchial wall area (P<0.001) were observed subsequent to bronchoprovocation. After bronchodilation, the increase in cross-sectional area (P<0.001) and the further increase in airway wall area (P<0.01) were significant in all groups. In PC20+ and PC20- asthmatics, significant differences (P<0.05) in PaO2, >10 mmHg between baseline and provocation were observed. In healthy persons, the PaO2 decrease was <10 mmHg (P>0.05). After histamine provocation, the decrease in FEV1 was measured in the PC20+ group, whereas a <20% FEV1 decrease was found in the PC20- and the control groups, respectively. No significant correlations were observed between radiological data and the results of pulmonary function tests. CONCLUSIONS: HRCT demonstrated bronchial reactivity in hyperresponsive patients and, unexpectedly, in healthy subjects. The applied pulmonary function tests failed to characterize bronchial reactions in the healthy subjects. Based on these results, HRCT is a useful tool by which to achieve a comprehensive understanding of the pathophysiological processes in asthmatic patients.

[HRCT and bronchial asthma: visualization of the pathophysiologic changes of the pulmonary parenchyma after inhalation provocation]. / HRCT und Asthma bronchiale: Visualisierung pathophysiologischer Veränderungen des Lungenparenchyms nach inhalativer Provokation.

PURPOSE: To characterize parenchymal lung affections morphologically in patients with asthma and healthy subjects by high -resolution computed tomography (HRCT) subsequent to histamine-triggered inhalation bronchoprovocation and salbutamol-induced broncholysis, and to compare the results with pulmonary function tests. MATERIALS AND METHODS: Fifteen asthmatics with bronchial hyperreactivity, with a > 20% decrease in FEV1 and a > 10 mmHg decrease in PaO(2) after bronchoprovocation (PC20%+), twelve asthmatics with a < 20% decrease in FEV1 and a > 10 mmHg decrease in PaO(2) after bronchoprovocation (PC20%-), and eight healthy persons without bronchial hyperreactivity underwent inhalation bronchoprovocation and broncholysis. Spirometer-triggered HRCT at high lung volumes was performed, and total and peripheral lung densities and the amount of solid lung structures, representing predominantly vessels, were measured. RESULTS: After bronchoprovocation, we observed significant decreases in total and peripheral lung densities in all groups (p < 0.0005), and a significant increase in lung densities subsequent to bronchodilation (p < 0.0002). The morphological alterations in solid lung structure were not significantly different after bronchoprovocation or broncholysis (p > 0.05), as compared to the baseline measurements. In hyperreactive patients, PaO(2) significantly decreased after provocation and significantly increased after lysis (p < 0.05). In PC20%+ asthmatics, a mean reduction of 27.8% in FEV1 was observed, which was < 20% in the other groups. No significant correlations were observed between radiological data and the results of pulmonary function tests. In healthy persons, we demonstrated highly significant parenchymal response to bronchoprovocation and broncholysis, which was not otherwise documented by pulmonary function tests. CONCLUSION: In both PC20%+ and PC20%- patients as well as in healthy individuals, HRCT was efficient in the evaluation of pathoanatomical alterations of the lung parenchyma subsequent to inhalation provocation. In healthy individuals, these parenchymal alterations were not documented by pulmonary function tests.

Value of negative spiral CT angiography in patients with suspected acute PE: analysis of PE occurrence and outcome.

The aim of this study was to analyze pulmonary embolism (PE) occurrence and retrospective clinical outcome in patients with clinically suspected acute PE and a negative spiral CT angiography (SCTA) of the pulmonary arteries. Within a 35-month period, 485 consecutive patients with clinical symptoms of acute PE underwent SCTA of the pulmonary arteries. Patients with a negative SCTA and without anticoagulation treatment were followed-up and formed the study group. Patient outcome and recurrence of PE was evaluated retrospectively during a period of 6 months after the initial SCTA, and included a review of computerized patient records, and interviews with physicians and patients. Patients were asked to fill out a questionnaire concerning all relevant questions about their medical history and clinical course during the follow-up period. Special attention was focused on symptoms indicating recurrent PE, as well as later confirmation and therapy of PE. Of the 485 patients, 325 patients (67%) had a negative scan, 134 (27.6%) had radiological signs of PE, and 26 (5.4%) had an indeterminant result. Of 325 patients with a negative scan, 269 (83%) were available for follow-up. The main reasons for loss to follow-up were change of address, name, or phone number, or non-resident patients who left abroad. Of 269 patients available for follow-up, 49 patients (18.2% of 269) received anticoagulant treatment because of prior or recent deep venous thrombosis (32.6%) or a history of PE (34.7%), cardiovascular disease (18.4%), high clinical probability (8.2%), positive ventilation-perfusion scan (4.2%), and elevated D-dimer test (2%). The remaining 220 patients, who did not receive anticoagulant medication, formed the study group. Of this study group, 1 patient died from myocardial infarction 6 weeks after the initial SCTA, and the postmortem examination also detected multiple peripheral emboli in both lungs ( p=0.45%; 0.01-2.5, 95% confidence interval). The PE did not occur in any other patient. In patients with suspected PE and negative SCTA without anticoagulant therapy, the risk of recurrent PE in this study was less than 1% and similar to that in patients after a negative pulmonary angiogram. Therefore, we conclude that patients can be managed safely without anticoagulation therapy; however, this approach may not be appropriate for critically ill patients and those with persistent high clinical suspicion of acute PE.

[Certification according to ISO 9001--waste of time or necessity?]. / Zertifizierung nach ISO 9001--Zeitverschwendung oder Notwendigkeit?

Quality management (QM) systems are widely established management tools in the industry and business world today. In the health care sector, the need for quality, the implementation of quality management systems and economic orientation of the hospital management are strongly encouraged. Centers of excellence are created to offer special medical services of the highest possible quality. Furthermore, there is a worldwide tendency to establish standards in clinical medical settings, in teaching profession and medical science. These trends make the implementation of a quality management system in health care system highly desirable. The present manuscript reviews the fundamental principles and concepts and the aims of internationally accepted QM systems. It focuses on the ISO-9000 certificates and the European Foundation of Quality Management (EFQM) model. The advantages and disadvantages are discussed. The resources necessary for installation of a QM system and the different phases of implementation are reported. According to the experience of several groups, QM systems can be reliably used in a radiology department and lead to continuous improvement of the quality of services.

Spiral computed tomography of pulmonary embolism.

Within the last several years, spiral computed tomography angiography (SCTA) of the pulmonary arteries has emerged as a noninvasive angiographic modality for the evaluation of patients with suspected pulmonary embolism (PE). SCTA is based on continuous computed tomography (CT) data acquisition during patient transport through the rotating X-ray tube and detector system, where scanning is performed in the time period in which the injected contrast material passes through the pulmonary arteries. Single detector spiral CT has a sensitivity of approximately 85-90% and a specificity between 88-95%. Sensitivity and specificity are very likely to increase with the use of multidetector spiral CT scanners that allow scanning of large lung volumes with a scan collimation as narrow as 1 mm. Currently, SCTA is most commonly used as a primary imaging method in patients with suspected PE, and as a second-line method in cases with inconclusive ventilation/ perfusion scintigraphy results. SCTA has proven to be cost-effective, especially in combination with ultrasound of the lower extremities. Limitations of the method include a decreased sensitivity for the detection of small isolated clots in the peripheral pulmonary arterial bed, and a potentially reduced image quality in patients with coexistent cardiopulmonary disorders. Despite these limitations, several studies have now documented that, in patients with suspected pulmonary embolism, it is safe to withhold anticoagulation therapy if a spiral computed tomography exam of the pulmonary arteries is negative and no lower extremity venous thrombosis is present. In the future, multislice computed tomography scanning of the pulmonary arteries with multiplanar reformation and one-stop shopping, i.e. scanning of the pulmonary arteries and the lower extremity veins in a single session, will further enhance the role of computed tomography angiography in the examination of patients with suspected pulmonary embolism.

Changes in lung parenchyma after acute respiratory distress syndrome (ARDS): assessment with high-resolution computed tomography.

The aim of this study was to evaluate the appearance, extent, and distribution of parenchymal changes in the lung after acute respiratory distress syndrome (ARDS) as a function of disease severity and therapeutic procedures. High-resolution computed tomography (HRCT), clinical examination, and lung function tests were performed in 15 patients, 6-10 months after ARDS. The appearance and extent of parenchymal changes were compared with the severity of ARDS, as well as with clinical and therapeutic data. Lung parenchymal changes resembling those found in the presence of pulmonary fibrosis were observed in 13 of 15 patients (87%). The changes were significantly more frequent and more pronounced in the ventral than in the dorsal portions of the lung ( p<0.01). A significant correlation was observed between the extent of lung alterations and the severity of ARDS ( p<0.01), and the duration in which patients had received mechanical ventilation either with a peak inspiratory pressure greater than 30 mmHg ( p<0.05), or with more than 70% oxygen ( p<0.01). Acute respiratory distress syndrome frequently is followed by fibrotic changes in lung parenchyma. The predominantly ventral distribution of these changes indicates that they may be caused by the ventilation regimen and the oxygen therapy rather than by the ARDS.

Equipment availability and diagnostic strategies for suspected pulmonary embolism in Austria.

The aim of this study was to investigate equipment availability and current diagnostic strategies for suspected pulmonary embolism (PE) in Austrian hospitals. A questionnaire was sent to the medical directors of all Austrian hospitals with emergency and/or surgical, orthopedic, and medical departments. The questionnaire contained questions regarding the available equipment suitable for the imaging diagnosis of PE, the first-line and second-line imaging tests for patients with suspected PE, and additional lower extremity venous imaging and laboratory tests that complement the diagnostic armamentarium. The return rate for questionnaires was 81% (127 of 157 hospitals). There were 97% of hospitals that had the equipment to perform sonography, 59% could perform pulmonary angiography, 54% spiral CT, 19% ventilation/perfusion (V/P) scintigraphy, and 4% perfusion scintigraphy alone. Spiral-CT angiography (SCTA) was the first-line imaging study for suspected PE in 56% of hospitals, followed by echocardiography and V/P scintigraphy. Lower extremity venous imaging (47%) and, interestingly, V/P scintigraphy (43%), served as second-line imaging tests. D-dimer tests were included in the diagnostic strategy in 74% of hospitals. Spiral-CT angiography is the most commonly used primary method for suspected PE in Austrian hospitals. The V/P scintigraphy is available only in a minority of hospitals to investigate patients with suspected PE. When V/P scintigraphy is available, however, it is employed in a large number of patients per annum.

Lung manifestation in asymptomatic patients with primary Sjögren syndrome: assessment with high resolution CT and pulmonary function tests.

The authors studied 37 consecutive patients with primary Sjögren syndrome and normal chest radiographs. Thin-section CT images were analyzed using a semiquantitative grading system. The presence, distribution, and severity of 9 morphologic parameters were assessed. In 34 patients, CT findings were correlated to pulmonary function tests (PFTs). Abnormal high resolution CT (HRCT) findings were seen in 24 of 37 patients (65%): interlobular septal thickening, n = 9; micronodules, n = 9; ground glass attenuation n = 4; parenchymal cysts, n = 5. Intralobular opacities, honey combing, bronchial wall thickening, bronchiectasis, and pleural irregularities were less frequent. Both HRCT and PFTs were normal in 10 patients. Computed tomography was normal in four patients with PFTs that indicated the presence of small airway disease. High resolution CT abnormalities were found in seven patients with normal PFT. The overall correlation between HRCT and PFTs was poor. High resolution CT and PFTs appear to be sensitive for both the early detection of parenchymal abnormalities and a decreases in lung function in asymptomatic patients with primary Sjögren syndrome. However, abnormal HRCT findings do not necessarily indicate a substantial alteration in PFTs.

Quantification of coronary artery calcification in patients with FH using EBCT.

BACKGROUND: Calcification of the coronary vessel wall is regarded as a marker of advanced coronary atherosclerosis. METHODS: To test whether patients with heterozygous familial hypercholesterolemia (FH) exhibit excessive calcification of the coronary vessel wall, we quantified coronary artery calcium in LDL-apheresis treated FH-patients with known severe coronary artery disease (CAD) (n = 10), in patients with moderate hypercholesterolemia and known severe CAD (n = 10), and in asymptomatic controls (n = 10) using electronic beam CT. The total coronary calcium score (Agatston-Score), the number of calcified lesions and the calcified plaque volume were evaluated for this study. RESULTS: CAD-patients with FH, although on average 10 years younger, had a significantly higher total coronary calcium score (702/2018/2890), number of lesions (34/43/49) and calcified plaque volume (700/1818/2313) compared to patients with CAD only (480/641/1362, 10/16.5/22, 480/588/1209, respectively) and controls (10/47/137, 2/4/10, 15/50/144, respectively). Furthermore, we observed a significant correlation (r = 0.93; P < 0.01) between LDL-cholesterol levels (pretreatment levels of the CAD-FH group) and the total coronary calcium score in all three groups. Our results demonstrate that coronary artery calcification is more extensive in CAD-patients with FH than in CAD-patients with moderate hypercholesterolemia. In addition, we provide evidence that the amount of calcium in the coronary vessel wall in FH patients result from a long lasting history of elevated LDL-Cholesterol levels. CONCLUSION: These findings emphasize the significance of LDL-cholesterol as a risk factor for atherosclerosis and underline the importance of early diagnosis of CAD and early cholesterol lowering therapy in FH patients.

Acute pulmonary trunk dissection in a patient with primary pulmonary hypertension.

Spiral CT imaging findings including multiplanar reconstructions of an acute dissection of the pulmonary trunk in a 22-year-old female patient with primary pulmonary hypertension (PPH) are presented and discussed.

Cystic fibrosis: CT assessment of lung involvement in children and adults.

PURPOSE: To compare a computed tomographic (CT)-based scoring system with nonimaging indexes of pulmonary status in patients with cystic fibrosis. MATERIALS AND METHODS: Pulmonary CT findings were assessed in 117 patients with cystic fibrosis, with cases classified according to three groups by age; 0-5 years, 6-16 years, and 17 years and older. Images were examined for specific abnormalities, and the severity and anatomic extent of each sign were used to generate a score. Scores in each category and the global score for each patient were correlated with pulmonary function test results, clinical status, serum immunoglobulin levels, and genotype, all obtained within 2 weeks of CT. RESULTS: The most frequent individual CT abnormalities were bronchiectasis in 94 (80.3%), peribronchial wall thickening in 89 (76.1%), mosaic perfusion in 71 (63.9%), and mucous plugging in 56 (51.3%) patients. The percentage of patients with specific CT findings and the overall CT scores increased significantly (P < .05) with progressively increasing age groups. All CT findings and the overall CT scores correlated significantly (P < .05) with the pulmonary function test results, serum immunoglobulin levels, and clinical scores. No relationship was observed between genotype and CT scores. CONCLUSION: Scoring of CT studies in patients with cystic fibrosis seems to offer a reliable way to monitor disease status and progression and may provide a reasonable tool to assess treatment interventions.

Thoracic venous anatomy delineated by malpositioned central venous catheters on plain chest films.

The aim of this essay was to demonstrate the thoracic venous anatomy as delineated by malpositioned central venous catheters on plain chest radiographs. We therefore used the didactic advantage of clinically inadvertent catheter positions. This approach was chosen to illustrate venous anatomy with plain chest radiographs, and, thereby, to recognize malpositions promptly on the modality with which positions of central venous catheters is routinely performed.

[Staging of bronchial carcinoma]. / Staging des Bronchialkarzinoms.

Staging of any tumor, i.e. determination of the extent of the disease, serves to select the patients who might profit from curative surgical intervention or to define those patients with inoperable carcinomas who should be referred for other therapies, such as chemotherapy or irradiation. Furthermore, accurate staging is necessary for assessment of prognosis, for radiation therapy planning, and for differentiation of those with small-cell lung cancer or for follow-up examinations of small-cell lung cancer patients after during and after chemotherapy. The primary radiological staging and diagnostic modalities for assessment of bronchial carcinomas are computed tomography (CT) of the thorax including liver and adrenal glands, abdominal sonography, and bone scintigraphy. Magnetic resonance imaging (MRI) should be reserved for specific indications, e.g. infiltration of the chest wall or staging of patients with intolerance/allergy to intravenous contrast medium. The clinical value of nuclear medicine techniques, such as [18F]2-fluoride-2-desoxy-D-glucose positron emission tomography (FDG-PET) for evaluation of lymph nodes and distant metastases, In-111 octreotide/somatostatin receptor scans for staging of small-cell lung cancer, and thallium-201 SPECT are currently being assessed in numerous studies, although these techniques are already in routine use. In future these or nuclear medicine techniques, as well as techniques using molecular-based contrast material, especially for MR imaging, currently in experimental status, may yield serious potential for staging purposes.

World Wide Web and Internet: applications for radiologists.

Global exchange of information is one of the major sources of scientific progress in medicine. For management of the rapidly growing body of medical information, computers and their applications have become an indispensable scientific tool. Approximately 36 million computer users are part of a worldwide network called the Internet or "information highway" and have created a new infrastructure to promote rapid and efficient access to medical, and thus also to radiological, information. With the establishment of the World Wide Web (WWW) by a consortium of computer users who used a standardized, nonproprietary syntax termed HyperText Markup Language (HTML) for composing documents, it has become possible to provide interactive multimedia presentations to a wide audience. The extensive use of images in radiology makes education, worldwide consultation (review) and scientific presentation via the Internet a major beneficiary of this technical development. This is possible, since both information (text) as well as medical images can be transported via the Internet. Presently, the Internet offers an extensive database for radiologists. Since many radiologists and physicians have to be considered "Internet novices" and, hence, cannot yet avail themselves of the broad spectrum of the Internet, the aim of this article is to present a general introduction to the WWW/Internet and its applications for radiologists. All Internet sites mentioned in this article can be found at the following Internet address: http://www.univie.ac. at/radio/radio.html (Department of Radiology, University of Vienna)